Minimum width towline with damage shield



Sept. 26, 1967 0. A. NICHOLS MINIMUM WIDTH TOWLINE WITH DAMAGE SHIELD 3 Sheets-Sheet 1 Filed Aug. 31, 1966 HTTORNEY Sept. 26, 1967 o. A. NICHOLS MINIMUM WIDTH TOWLINE WITH DAM AGE SHIELD 3 Sheets-Sheet 2 Filed Aug. 31, 1966 INVENTOR. DONALD A. NICHOLS xi Q 4 3 Sheets-Sheet 5 INVENTOR ATTORNEY S l 26, 1967 11A. NICHOLS MINIMUM WIDTH TOWLINE WITH DAMAGE SHIELD Filed Aug. 31, 1966 I I .llll ll I'll IH -Illllllllllll.

MMH Hm DONALD A; NICHOLS United States Patent Office 3,343,535- Patented Sept. 26, 1967 3,343,515 MINE [UM WlDIH TGWLINE WETH DAMAGE SHIELD Donald A. Nichols, Gld Lyme, Conn., assignor to the United States of America as represented by the Secretary of the Navy Filed Aug. 31, 1966, Ser. No. 57%,790 6 Claims. (Cl. 114--235) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to the towing of submerged objects commonly called fish such as sonar devices, for example, from a ship and particularly to an improved towline including a strength member with minimum-width sectioned fairing thereon and electrical cable housed Within the fairings and along the strength member. Strength member is a term used in the art to define the mechanical cable portion of the towline as compared to the electrical cable portion thereof and is so used in the description following. Sectional fairings is a term employed to designate fairings of several inches in length as compared to continuous fairings which may be 25 feet or more in continuous length.

The term ship as used herein is intended to include underwater surface or air ships. However, the invention is particularly useful in a towline connecting a fish and a surface ship and the invention will be described in relation to such application.

In towing a fish during naval operations, it is often necessary for the ship to move at high speeds during which water resistance or drag on the strength member and the fairing sections is considerable as is the force between adjacent fairing sections. The fairing, composed of many sections abutting end to end, prevents vibration of the strength member as the fish is towed at various speeds. The fairings also provide protection both in the water, and on the ship, for electrical cables passing through the fairing sections from the ship to the towed fish. Such towlines are required for operation of the sonar device of the fish from the ship.

It is a general object of the invention to provide an improved towline of the type described above.

A further object is to provide a towline incorporating the characteristics of minimum width and continuous complete protection of electric cables passing through the fairing sections.

Other objects and advantages will appear from the following description of an embodiment of the invention, and the novel features will be particularly pointed out in connection with the appended claims.

In the accompanying drawings:

FIG. 1 is a schematic view illustrating the manner of use of a sectionallly faired towline in towing a submerged object from a ship,

FIG. 2 is a perspective view of a portion of the towline carrying one fairing unit incorporating ribbon cable and constructed in accordance with this invention,

FIG. 3 is an exploded view of the fairing unit of FIG. 2 and also showing and associated section of strength member,

FIG. 4 is an elevation view of part of the towline, and illustrating two types of fairing units used in the towline and their connection to one another in a towline section, and

FIG. 5 is a sectional view taken on line 5-5 of FIG. 4.

In accordance with this invention, the stream-lined fairing units are pivoted on the strength member by having aligned passages in the units through and along which the strength member passes successively. Also passing through the fairing units are electrical conductors through which the ship maintains electrical communication with the towed body. The electrical conductors are in flat ribbon form disposed in wavy shape in the passages of the fairing units, adjacent the passages through which the strength member passes, and extend alongside the strength member. Limited fanning out between adjacent fairing units usually occurs when the strength member is flexed, as in use or when wound on a drum for storage, and slack is provided in the conductor ribbons within the passage of each fairing unit to enable such limited relative separation and approach of portions of adjacent fairing units.

In the illustrated embodiment of the invention shown in FIGS. 1 to 5 inclusive, and referring initially to FIGS. 1 and 2, the usual flexible strength member 1, in use passes from a drum 2 over an idler sheave 4 into the water indicated and at its free or lower end it is pivotally attached to an object or fish 5 to be towed submerged, the fish housing a sonar device, or other equipment (not shown). When not in use, the strength member 1 is wound on the hoist drum 2 on the rear part of a towing ship 3. On the strength member 1, in end to end abutting contact with one another, are a plurality of individual fairing units or sections extending from the towed object 5 to the hoist drum 2. These fairing sections comprise a plurality of support fairings indicated at 6 and spaced along the strength member 1 together with pluralities of additional rider fairing units 7, each plurality of fairing units 7 being supported by its next lower adjacent support unit 6. The strength member 1 is usually a wire rope formed of a helical wound bundle of flexible metal wires.

As shown in FIG. 3, the fairing units 7 comprise a nose piece 8, tail piece 9, a U-sh'aped coupling member 12, a support column member 13 and a clamping band 14. The tail piece 9 is formed with a central tongue 15 projecting in the direction of the U-shaped member 12 to be received in the groove 16 shown between the projecting leg portions of the U-shaped member 12. The support column member 13 is preferably formed of a strong low-friction plastic such as an acetal resin, for example, Delrin, concavely curved in the face 17 thereof facing the strength member to closely follow the contour of strength member 1 adjacent to the forward portion of the column member. A central groove 18 is formed in the portion of the column 13 adjacent its face 17 to receive the metal band clamp 14 and to bind between the U-shaped member 12 and the support column member 13 a plurality of electrical ribbon cables 19 which are provided to pass electrical current from the ship to the towed device.

To accommodate the flexing of the electrical cables 19, the tail piece 9 is formed with curved frontal surfaces 20 and 21, as indicated. Both the upper and lower side of the tail piece 9 are suitably recessed to accommodate the trailing edge portion of the nose piece and form substantial smooth flush surfaces when the tail piece is assembled in the nose piece. For example, an upper recess indicated at 22 is provided to receive the trailing edge portions of the sides 24 and 25 of the channel-shaped nose piece 8.

To provide for assembly of the fairing 7 on the strength member 1, fastener holes are formed in the tail piece 9, -in both sides 24 and 25 of the channel-shaped nose piece 8 and in the column 13. Thus, in the nose piece 8 are formed apertures 26 to 29 for alignment respectively with apertures 30 to 33 in the column 13. In the tail piece 9, apertures 38 to 41 align respectively with apertures 42 to 45 in the nose piece 8. Internally a threaded 3 hexagonal prismatic insert such as indicated at 51 is fitted into each of the fastener holes of the tail piece 9 and column 13. Pairs of fiat-head screws 51 and 52 are passed through the nose piece and threaded into opposite ends of each insert 50 to secure the fairing in assembled condition as shown in FIG. 2.

As shown in FIGS. 3 and 4, aligning rods 55 and 56 are provided in each tail piece 9 in staggered recesses 57 and 58 to maintain adjacent fairings in pivotal alignment. This feature Was disclosed in United States Patent No. 3,176,646 and is not per se a part of the subject invention.

. Referring to FIGS. 1 and 4, the support fairing 6 is the same in construction as described for unit 7 except that the unit 6 is provided with means for pivotally fixing the unit to the strength member such that each support unit can support a plurality of the units 7 located between it and the next support fairing nearer to the ship. Thus, as shown in FIG. 4, the nose piece 59 of the unit 6 is notched in its front face as at 61) to straddle a pivot connecting fixture generally indicated at 61. Fixture 61 comprises a sleeve, commonly referred to as a support ring, 62 which is fixed to the strength member 1 by any suitable means such as welding or cementing and suitable thrust bearing means such as thrust washers 63, 64, and 65. The fixture 61 transfers thrust load from the support fairing 6 to the strength member 1 while permitting all fairing sections 6 and 7 to pivot.

The support fairing 6 is provided with a support column indicated at 67 which has an end 67a which bears against the adjacent end 13a of column 13 of fairing 7. The columns 67 and 13 and tail pieces 9 extend beyond the edges 23 and 54 of the nose pieces 59 and 8 sufiiciently to prevent adjacent nose pieces from touching each other under all conditions of use in order to prevent mutual damage occurring to the nose pieces and to reduce friction between adjacent fairings under compression load. As in the case of nose piece 8, the nose piece 59 is secured to the column 67 and to its associated tail piece 9 through hexagonal shaped internally threaded inserts t) and associated screws 51 and 52 shown in FIGS. 3 and 4.

The towline thus far described is disclosed and claimed in copending applications entitled, Tow Lines With Minimum Width Pairings and Minimum Width Tow Lines With Stretchable Electrical Cable and Improved Clamping Means. The subject invention is directed to the improvement whereby continuous and complete protection is provided for the electrical cables passing through the fairing sections during all conditions of use and storage at all times.

Thus, referring to FIGS. 3, 4, and 5, shields 10 and 11 are provided for each fairing section. Shields 10 and 11 are slotted as at 34 to 37 align respectively with apertures 26 to 29 of the nose piece 8 and with apertures 39 to 33 of the column 13. Shields 10 and 11 are apertured as at 46 to 49 to align respectively with apertures 42 to 45 of the nose piece 8 and apertures 38 to 41 of the tailpiece 9.

As shown in FIG. 2, the shields 19 and 11 are positioned one on each side of the electrical cables 19 to protect the cables and are secured with the nose piece 8 and on opposite side of the column and tail Piece 9 by fastenings indicated at 50, 51 and 52. It will be noted as shown in FIG. 4, that each shield projects between the nose piece and electrical cables of the adjacent fairing section such that when the fairings are assembled on a strength member both sides of the electrical conductors are housed by the nose piece and the shields. Further, the shields are curved along the trailing edges thereof to permit continuous slid able couple with the adjacent nose piece when the fairings fan out during curvature of the cable in storage on the drum or in traversing the sheave. The column members 13 function as spacers for adjacent shields in a single fairing unit and adjacent engaging ends of the columns 13 function to establish pivot points from which the curved A portions 10 and 11 of the shields are developed to avoid interference in slidable operation of the shields. Both the upper and lower side of the tail piece 9 are'suitably recessed as at 2.2 and 22a to accommodate the trailing edge portions of the nose piece and shields and form smooth flush outer surfaces.

Advantage of the subject invention is the continuous and complete protection of the electrical cables from mechanical damage under all conditions of use or otherwise. Thus, in use under Water the electrical cables are protected from abrasion and the forces of passing water and in addition reduce drag on the fairing sections. In use on the Winch drum or in deck storage or repair areas the electrical cables remain protected.

It is to be understood that without departing from the broad aspect of the subject invention, shields can be provided in other configurations than shown in the preferred example illustrated in the drawings and that other means than the column 13 and tail piece 9 can be provided to space the shields on opposite sides of the electrical cable. However, it is to be noted that in the preferred embodiment shown in the attached drawings cooperation exists between the column 13, the tail piece 9 and the shields 10 and 11 in that the abutting relationship of the columns 13 provide pivot points from which the curved edges 10a and 11a of the shields are developed and curved surfaces 21 and 21 of tail piece 9 provide clearance for movement of the shields within the fairing units as the units fan out in operation. The shields are made of a suitable slightly flexible material resistant'to corrosion and the effects of salt water. Any of several plastics, as for example, polypropylene have been found satisfactory.

It will be understood that various changes in the details, materials, and arrangement of parts, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.

I claim:

1. A towline with fairings thereon by which a submerged object may be towed from a ship comprising:

a flexible strength member,

a plurality of electrical cables,

a plurality of fairing units each having a channel-shaped nose piece and a tail piece having a forward edge portion received in and closing the open face of said channel-shaped nose piece to define a passage for said strength member and cables,

means securing said cables in said fairings and pivotally securing said fairings on said strength member,

each of said fairings including a pair of shields fixed to the fairing on opposite sides of said cables and extending each slidably into the next adjacent fairing to provide continuous mechanical protection for said cables,

each of said shields being formed convexly arcuate along its trailing edge to avoid interference in fan spread of said fairings upon bending of said strength member.

2. A towline according to claim 1,

the forward edge portion of said tail piece being curved to closely follow the trailing edge curvature of said shields.

3. A towline according to claim 1,

each of said fairing units including a support column fixed to said nose piece and projecting beyond the side extremities thereof to fixedly space adjacent fairing units and by abutment of adjacent ends of adjacent support columns to form pivot points from which the arcuate trailing edge of said shields is developed.

4. A towline according to claim 1,

the forward edge portion of said tail piece being recessed to receive both the trailing edges of said shields and nose piece to form a flush outer surface of said fairing unit.

5 6 5. Atowline according to claim 1, cessed to receive both the trailing edges of said the forward edge portion of said tail piece being shields and nose piece to form a flush outer surface curved to closely follow the trailing edge curvature of said fairing unit.

of said shields,

each of said fairing units including a support column 5 Refereflces Cited fixed to said nose piece and projecting beyond the UNITED STATES P N S at 1 3,176,646 4/1965 Natwick et al. 114235 adjacent support columns to form pivot points from which the arcuate trailing edge of said shields is de- 10 MILTON BUCHLER, Primary Examiner veloped. 6. A towline according to claim 5 T. M. BLIX, Assistant Examiner.

the forward edge portion of said tail piece being re- 

1. A TOWLINE WITH FAIRINGS THEREON BY WHICH A SUBMERGED OBJECT MAY BE TOWED FROM A SHIP COMPRISING: A FLEXIBLE STRENGTH MEMBER, A PLURALITY OF ELECTRICAL CABLES, A PLURALITY OF FAIRING UNITS EACH HAVING A CHANNEL-SHAPED NOSE PIECE AND A TAIL PIECE HAVING A FORWARD EDGE PORTION RECEIVED IN AND CLOSING THE OPEN FACE OF SAID CHANNEL-SHAPED NOSE PIECE TO DEFINE A PASSAGE FOR SAID STRENGTH MEMBER AND CABLES, MEANS SECURING SAID CABLES IN SAID FAIRINGS AND PIVOTALLY SECURING SAID FAIRINGS ON SAID STRENGTH MEMBER, EACH OF SAID FAIRINGS INCLUDING A PAIR OF SHIELDS FIXED TO THE FAIRINGS AN OPPOSITE SIDES OF SAID CABLES AND EXTENDING EACH SLIDABLY INTO THE NEXT ADJACENT FAIRING TO PROVIDE CONTINUOUS MECHANICAL PROTECTION FOR SAID CABLES, EACH OF SAID SHIELDS BEING FORMED CONVEXLY ARCUATE ALONG ITS TRAILING EDGE TO AVOID INTERFERENCE IN FAN SPREAD OF SAID FAIRINGS UPON BEING OF SAID STRENGTH MEMBER. 